Newly-appointed Texas A&M head coach Kevin Sumlin speaks during a news conference officially introducing him as the NCAA college football team's new coach on Monday, Dec. 12, 2011, in College Station, Texas. Sumlin was hired to replace Mike Sherman who was fired two days earlier after a disappointing 6-6 season. (AP Photo/Bryan-College Station Eagle, Dave McDermand)

Photo By Karen Warren/Houston Chronicle

Texas A&M's new head coach Kevin Sumlin, who is not coaching the team today, before the start of the Meineke Car Care Bowl at Reliant Stadium,Saturday, Dec. 31, 2011, in Houston.

COLLEGE STATION - When Texas A&M officially announces Mark Snyder as its defensive coordinator, he should utter the same phrase he did about seven years ago when introduced as Marshall's head coach.

"We need that 12th man out there every Saturday in that stadium," Snyder said then.

On second thought, urging the 12th Man to show up at A&M - where the term "12th Man" is trademarked - is like telling Alabama coach Nick Saban he needs to get serious. It simply isn't required.

Saban and a host of other coaches of a handful of the nation's top programs await Snyder in his Southeastern Conference debut in September, and that's one thing Snyder, with no previous ties to A&M, has in common with the Aggies: Neither has any SEC experience.

Still, Snyder, 47, has shown a penchant for success in some rugged settings, primarily the Big Ten from 2001-04 as an assistant to then-coach Jim Tressel at Ohio State, the last season as Buckeyes defensive coordinator.

New A&M coach Kevin Sumlin will lean heavily on Snyder in the Aggies' first sojourn through the SEC, which has won the last six national titles.

Sumlin, a one-time offensive coordinator at A&M and co-offensive coordinator at Oklahoma, knows offense, and plenty of fans are curious to witness his plan of attack against the swift defenses of the SEC. That's also where his leaning on Snyder comes in.

Snyder, an Ohio native and a collegiate safety, spent five seasons as head coach at his alma mater Marshall - where he holds the record for interceptions in a season with 10 - and went 22-37 in that span. He quickly returned to his defensive roots as South Florida's coordinator the past two seasons.

The Bulls of the Big East ranked 17th nationally in total defense in 2010 and 39th this past season. Snyder employs a 4-3 scheme - four defensive linemen and three linebackers - in contrast to DeRuyter's 3-4 of the past two seasons.

In his lone season as a coordinator at a major program, Snyder's 2004 Buckeyes defense improved as the season wore on, and Ohio State wrapped up that year with a 33-7 victory over Oklahoma State in the Alamo Bowl.

"I saw a lot of growth every day," Tressel told the Columbus Dispatch of Snyder's improvement as a coordinator that season.

Since then, Snyder owns another five years of head-coaching experience, along with two more seasons as a defensive coordinator. Sumlin and the home of the 12th Man - the trademarked one - are banking on all of that experience in other leagues paying off in the SEC.

Quarterback Ryan Tannehill, a senior this past season, broke his foot while training, according to a person with knowledge of the situation. Tannehill won't take part in the Jan. 28 Senior Bowl because of the injury. He's also set to get married Saturday, and that's still on.

Tannehill is projected as a first- or second-round pick in this spring's NFL draft. He broke A&M's single-season passing record with 3,744 yards in leading A&M to a 7-6 finish in 2011 and is the school's most accurate passer in history (completing 62.5 percent).